Improvement in machines for grinding clay



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Patented April 2,1872.

, `A ALEXANDER. l mprovementin Mahinesbr Gfindng Cly, &c. No.125J59.

v @Ni ABRAM ALEXANDER, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO HIM- SELF, JOSEPH A. ROBINSON, AND JAMES EWING, OF SAME PLACE.

IMPROVEMENT IN MACHINES FOR GRINDING CLAY, &c. l

Specification forming part of Letters Patent No. 125,159, dated April 2,1872; antedated March 26, 1872.

SPECIFICATION. To all 'whom t may concern:

Be it known that I, ABRAMV ALEXANDER,

of the city of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improved Machine for Grinding, Mixing, and Tempering ltock, Clay, 8vo.; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawing making a part of this specication, in which- Figure l is a side elevation of my machine. Fig. 2 is a longitudinal vertical section thereof. Fig. 3 is a face view of one of the grindin g-rolls. Fig. 4 is a perspective view of the mixing-pan and stirrers; and Fig. 5 illustrates the mode of changing the angle at which the stirrers operate.

Like letters of reference indicate like parts in each.

rIhe nature of my invention consists in the construction of a machine for grinding, mixing, and tempering rock, clay, Ste., for use in been properly tempered and mixed.

To enable othersA skilled in the art to make and use my invention, I will proceed to describe its construction and mode of operation.

The frame-work A, by which the devices are supported, may be of any suitable or convenient construction, as also the uprights B and hopper O. In boxes set in the uprights B I adjust the spiral-toothed grinding and` crushing rollers D D', so that their spiral teeth shall mesh into each other and one roller operate the other at the same time that the material is passing through without the use of other gear for th at purpose. The form of the doublespiral teeth is shown in Fig. 3. Motion is communicated to one of these rollers by an endless screw, E, on the main vdriving-shaft E,

which plays into a gear-wheel, D, on the roller, D. The rock, clay7 or other material, as it passes through between the spiral teeth of the rollers D D', is subjected to both a crushing and a grinding force, and consequently can be more perfectly reduced from a lump or rock to a pulverized condition. But to secure `a more perfect pulverization I arrange under the rollers D Dl another pair of rollers, F F', having plain or smooth faces, one somewhat larger than the other,` and communicate mot-ion to one of them by a gear-wheel and screw-thread on the shaft E of the form above described. By gearing up only the smaller roller F and operating the larger roller F by frictional contact alone, I secure not only an increased biting or crushing operative area between the two, but also secure a slight grinding effect, as the tendency ofthe larger roller material to` fall down an apron, m', whence it is caught by buckets a on an elevator, a, carried up' and discharged into the mixin g-pan G. This mixing-pan G is placed horizontally, and has a vertical shaft, g, extending up through it along its axial line, and also along the axial line of the pug-mill H immediately below. On the upper end of the shaft g is a gear-wheel, g', which is operated by ascrew-thread, g, on the main driving-shaft E. At or near the mouth of the pan G a series of arms, a, extend radially out, and each arm c carries a number of Aflat-bladed knives or stirrers, a', which cut edgewise through the clay in the mixing-pan, though by the means presently to beY described these knives or stirrers may be set at a slight angle. Just above the arms a a collar, c, is adjusted on the shaft g, sufficiently tight to rotate with it. but not so tight but that it may be shifted slightly. To the under side of this collar c, near its periphery, by a `wrist or ball-and-socket or other like joint, is

attached a series of shifting-bars, d, each one of which is so adjusted as to be parallel with and a little behind one of the arms a. From the shank of each of the blades or stirrers a (the journal of each blade'workin g freely in its arm e) a shifting-lever, e, extends to its shiftin g-bar d, and is loosely pivoted thereto, while it is rigidly fastened to the shank of the stirrer af. The collar c has a lever, c', attached to it, by which it is rotated a short distance either way. By shiftin g the collar c the shiftin g-bars d receive a slight motion in the direction of the length and tangentiall y to the collar o. This motion causes the rear ends ofthe levers e to be moved toward or from the vertical shaft g, and by this motion the stirrers a receive a slight rotary motion on their axes or bearings which pass through the arms et. In this way these stirrers a are caused to pass through the clay in the mixing-pan either edgewise or at a slight angle, as may be preferred. Above the collar c I place a watertank, j', fix it tight to the shaft g, and extend out from it a perforated pipe, t', over each stirring-arm a, the perforations being so arranged that jets of water will be discharged into the tracks lf the stirrers a. Such devices for supplying water may be arranged in such number as may be desired over each arm a or over every alternate arm. In this way the clay is tempered to the proper consistency and finally worked toward the center of the mixing-pan, whence it passes down into the pug-mill H, where it is further operated on by the inclined blades S in the usual manner, and discharged through apertures k at the bottom, which may be opened or closed at pleasure by gates w. It is then ready for the molds. lhe pug-mill H I make slightly haringthat is, enlarged somewhattoward its lower end. This outward spread or enlargement is but slight, however, and facilitates the discharge of the ltempered clay.

The angle which the double-spiral teeth z on the rollers D D make with each other may be varied at pleasure, as also the relative size of the smooth rollers F F', ,so long as they be not of the same size. By the use of an elevater, a, for carrying the pulverized clay from the crushing-rolls upward and discharging it into the mixing-pan, I am enabled to arrange all my machinery on the same floor or foundation, and so `save expense in building.

I am aware that plain-faced crushing-rolls are not by themselves new, and that pinionwheels having double-spiral gear-teeth have been used in driving machinery, and also that a mixing-pan has been supplied with water through the driving-shaft, which was made hollow for that purpose. These features of' themselves I do not claim as new.

Vhat I claim as my invention, and desire to secure by Letters Patent, is-

1. The collar c, arranged on the vertical shaft g, with its shifting bars d, the latter being connected by shifting-levers e with the shanks of the stirrers a, for adjusting them to any desired angle, substantial] y as described.

2. rIhe construction and arrangement ot' an elevator, n, between the crushing-rolls F F and mixing-pan G, and on the same level or floor with both, substantially as described.

3. The water-supply tank j', arranged on and outside of the shaft g, above the mixing-pan Gr, in combination therewith, and with pipes t' and stirrers a', substantially as described.

4. rIhe main driving shaft E, having a double arrangement of screw-threads, arranged with reference to wheel g on shaft g and the gearing of the rollers D Dl F F, so as to communicate power to all, substantially as described.

In testimony whereof', I, the said ABRAM ALEXANDER, have hereunto set my hand.

ABRAM ALEXANDER.

Witnesses:

THos. B. Kuna, B. G. CHRIs'rY. 

